Front Wheel Bearings With Oil-Filled Hubs; Air Conditioning System - GMC TopKick 2007 Owner's Manual

Front Wheel Bearings with
Oil-Filled Hubs
Notice: If you drive your vehicle through deep
water that is higher than the front or rear
axle, water may enter the axle housing and
cause the axle lubricant to break down.
This could damage the gears inside. Avoid
driving your vehicle through deep water.
You should avoid driving your vehicle through
deep puddles or standing water. If you must drive
through water that is higher than the front or
rear axle, see your dealer immediately afterward
to have the condition of the axle lubricant checked.
If your vehicle has
oil-filled hubs,
occasionally check to
see if they have enough
oil. You can tell if there is
oil there by using the
circular gage on the
sight glass.
If there isn't, clean the rubber fill plug in the center
of the glass, and then remove it. Be careful not
to allow any dirt or water to get into the oil.
Add enough of the recommended oil to bring it up
to the level mark that you'll see on the glass.
Refer to your Maintenance Schedule for the proper
oil to use.
When you fill the hub, check the glass again after
driving a short distance. It takes a while for the
oil to flow through the system, and you may
find that you have to add a little more to fill it to
the proper level. Be sure not to overfill the hub.

Air Conditioning System

Every now and then, have your dealership check
your air conditioning system to be sure it has
not lost any cooling ability. If you think the system
is not working properly, have your GM dealer
check it out as soon as possible.
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